2.3.2.2 Contractual capacity The contracts concluded by persons without capacity to contract will be void ab initio.120 The presumption is that every person entering into a contract has a legal capacity to contract, unless the contrary is proved, the burden of proving lack of capacity lies on the party setting it up as a defence.121 Parties must have capacity to perform juristic acts to be able to form a contract, in particular, capacity to bind themselves.122 A juristic act means an act which is intended to have, and has legal consequences, when it is performed, a legal obligation is created, altered or terminated.123 2.3.2.3 Lawfulness It is a fundamental principle of law that a thing done contrary to the direct probation of law is void and has no legal force and effect,124 and as such, an agreement contra bonus mores is invalid and unenforceable.125 It is a general rule that agreements are prohibited by common law if they are against public policy or contra bonos mores, other contracts are statutorily prohibited.126 It was held in the case of Reeves v Marfield Insurance Brokers CC,127 that illegal agreements are not legally enforceable. 2.3.2.4 Physical possibility The general rule with physical impossibility is impossibilium nulla obligation est,128 meaning a contract is void if performance is impossible at the time of its inception. 129 In deciding whether performance of a contract is impossible, the law looks at the substance rather than form.130 The performance envisaged by the agreement should be impossible.131 The position that obtains is that if the court finds that the impossibility 120 Jason (2004: 30). Serobe v Koppies Bantu Community School Board 1958 (2) SA 265 at 271-272; Nagel et al (2000: 166). 122 Sharrock (2011: 39). 123 Sharrock (2011: 1). 124 Sierhout v Minister of Justice 1926 AD 99 at 109. 125 Nino Bonino v De Lange 1906 TS 120 at 125. 126 Gibson (1997: 10). 127 Reeves v Marfield Insurance Brokers CC 1996 (3) SA 766 at 775. 128 Hersman v Shapiro & Co 1926 TDP 367 at 375-377. 129 Gibson (1997: 56); Peters, Flamman &Co v Kokstad Municipality 1919 AD 427 at 434; Aird v Hockey 1936 EDL at 117. 130 Christie (2001: 106). 131 Rosebank Mall (Pty) Ltd v Cradock Heights (Pty) Ltd 2004 (2) SA 353 at 383. 121 14